Inconel is a nickel-chromium based super alloy. It is an alloy very resistant to oxidation and corrosion and which is particularly well suited for use in extreme environments with high pressure and high temperatures (over 800°). In particularr, it keeps its strength in a very wide temperature range.
It is used in particular for turbine wings, seals, heat exchangers and in the nuclear field.
Inconel is supplied in both spring and non-spring quality. In the spring quality, and depending on the varieties, it must undergo stress relief anneals at high temperatures for sometimes quite prolonged times. Inconels are available in sheets or in wire.
There are several varieties of Inconel (about 25), the most frequently used of which are :
- Inconel 600 (Ni72Cr14Fe6Mn1 – AMS5665 of AMS5687) has good resistance to oxidation and corrosion at high temperature. It is used for high temperature static applications. The finished parts must undergo a heat treatment at 460° for one hour. It is used in furnaces, the chemical, food and nuclear industries.
- Inconel 625 (Ni58Cr22Fe5Mo9Nb) has an excellent resistance in all corrosive environments. It is particularly suitable for salt water applications. The finished parts must be heat treated at 370° for 1 hour. The Inconel 625 is available in sheets or wire. It is used in the marine, space, chemical and nuclear industries.
- Inconel 718 (AMS5662, AMS5663, AMS5832 and AMS5962) has good resistance to high temperature creep rupture. It is stronger than the Inconel 750. It can be supplied in varying degrees of hardness and finished parts should be heat treated, depending on the conditions, between 620° and 1330° between 1 hour and 8 hours. It is well suited for dynamic high temperatrue applications.
- Inconel X750 (AMS5667 – AMS5671) has very good resistance for dynamic high temperature applications and good resistance for cryogenic temperatures (-200 to +700°). The finished parts must undergo a heat treatment at more than 700° for a least 16 hours. It is used for nuclear reactors, gas turbines, rocket engines and aircrat structures.
Filame works Inconel mainly in the form of wire and, in particular, has extensive expertise in springs for seals in the chemical, oil and aeronautical industries.